Inking mechanism of intaglio-printing machines



Feb. 24, 5 N W N 1,794,316

INKING MECHANISM OF INTAGLTO PRTNTING MACHINES Filed Aug. 12, 1929 2 Sheets-Sheet l Feb 24, 1931. 5 NEWTON 1,794,316

INKING MECHANISM OF INTAGLIO PRINTING MACHINES Filed Aug. 12, 1929 2 Sheets-Sheet 2 jmrenimf Patented Feb. 24, 1931 UNITED STATES PATENT omes am NEWTON, or ALTRINCHAM, ENGLAND, ASSIGNOR mo LINOTYIPE AND MACHINERY LIMITED, or LONDON, ENGLAND INKING MECHANISM OF INTAGLIO-PRINTING MACHINES 'Application filed August 12, 1929, Serial No 385,375,, and in Great Britain August 14, 1928- p This invention "relates to mechanism for inking the plates of intaglio printing machines and has among its principal objects to provide new or improved automatically operatir'rg means for applying the inkto the said plates, preventing any such accumulation of ink on the plates as would impair the printed matter to be produced, and moving the doctors out of and into operative contact with the plates and simultaneously therewith, re-

spectively stopping and restoring the supply of ink to said plates.

The invention is particularly applicable to a machine of the two-revolution type 5 d5 wherein it is desirable to remove the doctor out of contact with the plate during the second or non-printing revolution of the plate cylinder to'avoid unnecessary wear of said doctor and plate. For that reason, the following description deals with a constructional form in which the invention is applied to a machine of said two revolution type ;-its

applicability to machines of other types will, however, be readily recognized.

The invention will now be described by reference to the accompanying drawings in which Figure 1 is a side elevation representing the improved inking mechanism as applying ink to theplate cylinder; v V

Figure 2 is a view similar to Figure 1 showing in full lines the position of the inking mechanism duringthe period at" which the gap in the plate cylinder is passing it, and diagrammatically indicating by dot-and-dash lines the position of the parts during the nonprilnting revolution of the plate cylinder, an

. Figure 3 is a transverse vertical section through the ink trough and adjacent parts, drawn to a large scale.

a The inking, in accordance with the present invention,-is effected by bringing into actual contact with the printing surface on the plate cylinder 1, a body of ink 3, contained in a well or trough of which the doctor 4 forms one wall and a movable floor 5 in ink-tight contact along one of its edges with said doctor, constitutes another wall. The ends of the ink trough are formed by two walls or brackets 'the ink thereby prevented from 6 which are perforated and provided with overflow pipes as at 7, for limiting the amount of ink inthe trough.

Thetrough floor 5 is secured to a bar 8, which is guided in slots 9 in the brackets 6 parallelly with the inclined plane of the doctor 4, so that, whatever be the position of this floor, ink-tight contact will always be maintained between it and the said doctor.

To each end ofthe bar 8,there is attached the lower end of an inclined rod 10 which is longitudinally slidable in a lug 11 on the respective bracket 6. The upper end of this rod carries a runner or anti-friction roller 12 on which a cam 13, fast to the plate cylinder 1, acts to depress the parts 10, 8 and 5, antagonistically to a helical spring 14 which bears at respectively opposite ends against the head of the said rod and against the lug 11. It will be noted that the cam 13 is of such shape that it serves to depress the trough floor 5 and retain it depressed, during the period at which the gap 2 of the plate cylinder 1 is passing the ink trough, (as indicated in full lines in Figure 2), so that the level of the ink in the latter is correspondingly lowered and being deposited on the plate 1' in advance, or to the rear of the desired or actual printing area.

- The plate 1 encircles the cylinder 1, ends being secured within the gap 2, by suit able clamping and straining devices which, of themselves, form no part'of the present invention. I

The ink trou h is adjustably carried by arms 15 pivote about the. stationary axis of a shaft 16 by which it can be reciprocatedparallelly with the axis of the plate cylinder 1 so that the doctor 4 will be caused to slide along the surface of the printing plate .1 at the same time as said plate is being rotated past it, and thereby avoid scoring of the plate as might ocpur were this relative longitudinal movement of doctor and plate not provided for. The means for impartlng the ust-named longitudinal movement to the doctor 4 are not represented in the drawings,

and may be of any desired construction.

The arms 15 together with the several parts carried thereby, are raised by cams or eccentrics 17 (one at either side of the machine) which are oscillated in such manner, or at such times, that the doctor 4 and ink trough are brought into operative relation to the printin plate, only at alternate revolutions of the p ate cylinder 1; the arms 15, in the arrangement illustrated, merely rest on the cams 17 so that the descent of the ink trough is effected by gravity only, but, if desired,

other means may be provided for securing the lowering of the ink trough.

The cams or eccentrics 17 are fast on a rock shaft 18 which receives its oscillating motion through a spur wheel 19 (also fast on said shaft) and a toothed sector lever 20 turning about a fixed pivot 21 and provided with a roller 22 which is engaged in the groove of a cam 23 whose shaft 24 is rotated once for H every two revolutions of the plate cylinder 1.

The sector lever 20, has pivoted to it, the lower end of a link 25, whose upper end is similarly connected to a lever arm 26 fast to a transverse rock shaft 27 which, at either end, carries a bent arm 28 adapted. to depress the respective spring-pressed push rod 10, and with it, the trough floor 5. As this lowering of the trough floor 5 by the bent arms 28 relatively to the trough itself occurs simul-- taneously with the lowerin of the trough by the turning of the cams 1 it will be seen that the level of the ink in the trough is wheel 32, swings the ink trough as a whole,

about the axis of said shaft, to bring it up to or away from the plate cylinder 1. Furthermore, the doctor 4 is capable of being finely adjusted in the direction of its inclined plane, to vary the pressure exerted by it on the printing plate; in the example illustrated, this is provided for by supporting the docg tor on a bar 33 to which screws 34 are journalled which, when turned by their heads 35 (only one suchscrew is shown in the drawings) are threaded through nuts 36 in fixed relationship to the shaft 29.

An eflicient supply of ink is maintained by a pump 37, through a delivery pipe 38 which overhangs the ink trough and any surplus ink from this latter, is returned to the sump 39 from which the pump draws its supply, by

' way successively of the overflow pipe 7, a

- tray 40, pan 41 and gutter or channel 42. The

quantity of ink delivered to the ink trough may be regulated by any convenient means,

such as a relief valve or cook in the delivery pipe 38, which may be opened to a greater or less extent for releasing the desired proportion of the pump-propelled ink to enable it to flow back into the sump 39.

From the foregoing it will be seen that as the movement of the ink well or trough towards and away from the printing surface, is according to'the present invention, a function performed during each normal operative cycle of the machine, said invention is clearly distinguished from machines in which, as has heretofore been proposed, ink containers are moved into and out of operative relation to continuous cylindrical printing surfaces only at the commencement and termination of printing operations, and in which, owing to the continuous character of the printing surfaces, it has been unnecessary to provide for any such cyclical movement of the ink containers as that with which the present invention is concerned.

Having described my invention, I declare that what I claim and desire to secure by Letters Patent is 1. In an intaglio r-inting machine in which the printing sur ace is inked by movement through ink contained in a trough, the combination with an ink trough of means adapted to move said trough towards the printing surface during each normal operative cycle of the machine.

2. In an intaglio printing machine, the combination with a rotating printing surface and an ink trough by movement through which said surface is inked, of means adapted to move said trough during each normal operative cycle of the machine, into and out of the operative position in which the ink contained therein contacts directly with the printing surface.

3. In an intaglio printing machine, the

combination with a printing cylinder having a gap and a printing plate secured around said cylinder with its opposed ends located in said gap, and an ink trough through wh ch the plate passes during rotation of the cylinder, of means adapted to move the trough,

when said gap is passing therethrough, out of the operative position in WlllCh the ink contained in the trough contacts directly with the printing surface- -4. In an intaglio printing machine, the combination with a rotating printing surface and an ink trough by movement through which said surface is inke'd, of means operative during every alternate rotation of the printing surface to maintain said trough out of the operative position in which the 1nk contained therein contacts directly with the printing surface.

5. In an intaglio printing machine, the combination with a printing cylinder having a gap and a printing plate secured around said cylinder with its opposed ends located in said gap,and an ink trough through which the plate passes during rotation of the cylinder, of means adapted to move the trough,

when said gap is passing therethrough, out

of the operative position in which the ink contained in the trough contacts directly with the printing surface, and means operative during every alternate revolution of the printing cylinder to maintain the trough out of said operative position.

6. In an intaglio printing machine, an ink well or trough of which one wall is constituted by the doctor and another wall is constituted by a floor which is adjustable relatively to the doctor and is in ink-tight contact therewith in all positions of adjustment.

7. In an intaglio printing machine of the two revolution type, the combination with an ink well or trough of which one wall is constituted by the doctor and another wall is constituted by a floor which is adjustable relatively to the doctor and is in ink-tight contact therewith in all positions of adjustment, of means adapted to depress the floor of said trough independently of the trough itselfand maintain it depressed during every alternate revolution of the printing cylinder.

8. In an intaglio printing machine, the combination of an ink well or trough of which one wall is constituted by the doctor and another. wall is constituted by a floor which is adjustable relatively to the doctor and is in ink-tight contact therewith in .all positions of adjustment, of means adapted to depress simultaneously the trough and its floor to relatively varying extents.

. 9. In an intaglio printing machine of the two revolution type, the combination with an ink well or trough of which one wall is constituted by the doctor and another wall is constituted by a floor which is adjustable relatively to the doctor and is in ink-tight contact therewith in all positions of adjustment, of means adapted to depress the trough floor independently of the trough itself during each revolution of the printing cylinder, and supplemental'means adapted to depress simultaneously the trough and its floor to relatively varying extents during every alternate revolution of said cylinder.

-10. In an intaglio printing machine, the combination with a printing cylinder having a gap and a printing plate secured around said cylinder with its opposed, ends located in said gap, of an ink trough comprising one wall which constitutes the doctor for the printing surface and-another wall COIlStltllt-r ing the floor of thetrough which is adjustcombination with a printing cylinder having a gap and a printing plate secured around said cylinder with its opposed ends located in said gap, of an ink trough comprising one wall which constitutes the doctor for the printing surface and another wall constituting the floor of the trough which is adj ustable relatively to the doctor and is in inktight contact therewith in all positions of adjustment, means adapted to depress the floor of the trough when the cylinder ap' is passing the trough to lower the ink t erein out of contact with the printing surface, means operative during every alternate revolution of the printing cylinder to maintain the doctor out of contact with the printing nature hereto.

- SAM NEWTON.

able relatively to the doctor and is in inktight contact therewith in all positions of adjustment, and means dapted to depress the floor of the trough w en the cylinder gap is passing the trough to lower the ink therein out of contact with the printing surface.

11. In an intaglio printing machine, the 

